Essential System Administration Pocket Reference

The root Account

su	su [-] [user] [-c "command"]Run a command as another user (defaults to root). If no command is specified, a new shell is started. If the initial hyphen is included, then the user’s login environment is duplicated.
	Limiting access to su
	AIX:	Limited to groups listed in the sugroups attribute for root in /etc/security/user.
	FreeBSD:	Define the member list for group 0 as non-null.
	Linux:	Use the pam_wheel module in the su file.
	su log file
	AIX:	/var/adm/sulog	FreeBSD:	/var/log/messages
	HP-UX:	/var/adm/sulog	Linux:	/var/log/messages
	Solaris:	Specified in the SULOG setting in /etc/default/ su.

Limiting direct root logins to the console

AIX:	chuser ttys="/dev/lft,/dev/tty0" rlogin=false root
FreeBSD:	Omit secure from all entries in /etc/ttys except console.
HP-UX:	/etc/securetty lists devices where root is allowed to log in (omit “/dev/” from the names).
Linux:	Use the pam_securetty module.
Solaris:	/etc/default/login: CONSOLE=/dev/console

Granting Limited root Powers

sudo†	sudo [options] command
Run the specified command using the sudo facility. After successfully entering his password, a user can use the sudo command without having to re-enter it for a grace period (defaults to 5 minutes).
	Options
	-v	Reset the grace period to its full length.
	-K	Terminate the grace period.
	-u user	Run the command as the specified user (rather than root).
	-l	List allowed commands for the current user ...